Problem:

When opening a Word document two application windows for MS Office will open: one containing the document and the other just blank MS Office with no documents or a blank 'Document1' titled document.

Solution:

Open Microsoft Word and click the Office Icon (top left corner)
Click Word Options
In the windows that opens, click on Advanced
Scroll down to Display and then uncheck the Show all Windows in the task bar

Note: This fix will work for other products in the Microsoft Office Suite